A helicopter carrying North Sea oil workers crashed off the coast of southwest Norway on Friday, killing all 13 people on board, rescue services said, reports AFP. The Super Puma chopper went down around midday in the archipelago off the coast of Bergen, Norway's second-biggest city. Rescue services recovered eleven bodies but called off the search for the two remaining passengers five hours later saying they could not have survived the crash. "We presume that all 13 are dead," Borge Galta, head of the rescue centre in the southwestern Sola region told AFP. The cause of Norway's worst helicopter accident in decades was not immediately known, but investigators seemed to be leaning towards a technical problem. The aircraft was carrying 11 Norwegians, one Briton and one Italian, rescue services said. The helicopter broke into pieces near a small island and debris was found scattered on land and at sea.